System of distribution.



No. 890,593. PATEN'IED JUNE 16, 1908.

A; H. ARMSTRONG. v SYSTEM OF DISTRIBUTION.

APPLICATION FILED SEPTflS, 1807.

I/I/ZTZVESELEZ' [NT/ENTER V g & ALBERT HAHA ISTHUNG.

A TY

- To all whom it may concern:

- that of t e trolley wire.

UNITED sTArEs ATENT OFFICE.

ALBERT H. ARVS'lltONG, ()l SOlIlCNlCt/"lADY, NEW YORK, )iSSIGNOli 'lO (rEXERAL-lCLlClZ'l lIlH COMPANY, A CORPORATION Ol NEW YORK.

SYSTEMOF DISTRIBUTION.

Specification of Letters Patent.

Patented June 16, 1908.

Be it known that I, ALBERT H. ARM- STRONG, a citizen of the United States, resi l ing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Systems oi Distribution, of which the following is a specification.

My invention relates to alternating-current distribution, and particularly to railways operated by alternating current. If a lowvoltage conductor, such as a telegraph or telephone wire, extends in close proximity to a conductor carrying single-phase alternating current,'the low-voltage conductor is subject to disturbances due to induction both static and magnetic. Thus, in a single-phase alternating-current railway a telegraph wire on thesame poles with the working conductor is subject to such disturbances. T he disturbances due to ma netic induction are lar ely avoided when su stations are connecter to both ends of the working conductor. For instance, if a section of the working conductor extending between two sub-stations is considered, it will be seen that with a car in the middle of the section, the current in one half the section will neutralize the inductive' effect of the current in the other half, and whenthe car is not in the center the tendency to neutralization continues, since when the car is nearer one end of the section than the other, the shorter part of the section carries a greater current.

The object of my invention is to provide in such a system a simple arrangement for preventing the disturbing eflects of static induction. In accomplishing this I make use of the catenary, which is usually em loyed in the suspension of trolley Wires, an provide means for maintaining this catenary at a potential a proximately equal but 0 posite to That is, Ikeep the catenary at the same potential as the trolley wire, but with its potential wave displaced ap roximately 180' degrees from that of the tro ley wire. Under this condition, a telegraph or telephone wire located in proximity to the trolley wire will be subject to the static inductive effect of both the trolley wire and the catenary, and owing to the fact that the voltage of these conductors is at every instant approximately equal but opposite the resultant ell'oct on the adjacent telegraph or other wires will be 711' Z.

In carrying out my invention I provide insulation between. the catenary and thetrolley wire and connect these wires to ground through the coils ofa transformer. In this waya potential may be at all times maintained on the catenary equal to the potential on the trolley wire but with its wavedisplaced 180 degrees from the wave *of the trolley wire.

My invention will be most easily understood from reference to the accompanying drawing which shows diagrammatically a system of distribution on a single-phase railway, arranged accor-ding to my invention;-

Referring to the drawing, 1 is a trolley wire furnishing alternating current, this wire be ing supported from a catenary 2 in any usual and we 1 known manner, except for the fact that the trolley wire and the catenary are insulated from one another. For the pur pose of insulation between, the catenary and trolley wire, strain insulators 3 may be interosed in the wires by which the trolley wire 18 suspended from the catenary, or any other suitable arrangement may, be used for the same pur ose. The alternating current generator, w 'ch furnishes current'for the line, is indicated at 4 and is shown connected to the trolley wire on one side, and to the ground or track on its other. The trolley wire is connected to ground through the primary 5 of a transformer, and the catonary is connected to ground through the secondary 6 of this transformer, as shown diagrammatically in the drawings. Telephone, telegraph or other wires are indicated at 7 supported on the same poles as the trolley wire.

The operation ofthe system of distribution illustrated will be clear from the foregoing description. The transformer will impress a potential on the catenary equal to the poten tial on the trolley wire, but with its potential wave displaced ap roximately 180 degrees from that of the trolley wire. The telegraph or other wires will be subject to the static inductive effect of both the trolley wire and the catenaryand, as above explained, these will practic-all counteract one another.

What claim as new and desire to secure by Letters Patent of the United States, is-

low

noting current, a trolley Wire. -& cotenary susformer through the coils of which the trolley pension thcrvlor, and means for mointaining 1 and oatennry are connected to ground tho oatonnry at a potential zrpproxi1natcly j In witness whereof, I have hereunto set equal but opposite to that of the trolley wire. my hand this 11th day of So Jtomber, 1907. 2. Ina railway systemoporzrted by alter- ALBERT H. ARMSTRONG.

nating current, a trolley Wire, :1 catena-ry for j VVitnes'qes:

suspending the same, insulation between the 1 BENJAMIN B. HULL,

ootenory and the trolley Wire, and a trans MARGARET E. VNOOLLEY. 

